Highly ordered self-organized dot patterns on Si surfaces by low-energy ion-beam erosion

Scanning force microscopy (AFM) and high-resolution transmission electron microscopy (HRTEM) have been used to investigate the complex topography evolution of Si surfaces during low-energy ion beam erosion. Depending on ion-beam parameters, a variety of different topographies can develop on the surface. At oblique ion-incidence angles, nanodots are formed for ion energies ⩾ 300 eV upon sample rotation. Properly chosen parameters of the broad-beam ion source result in dots possessing a very high degree of lateral ordering with a mean dot size λ ∼ 30 nm . Both, degree of ordering and size homogeneity of these nanostructures increases with erosion time leading to the most ordered self-organized patterns on Si surfaces reported thus far.